Bf109 information, lighting a fuse and running for cover!

Originally Posted by Kurfürst

Rather badly researched and biased article I'd say with a large amount of clear errors, ie. the production number of Bf 109G, no Spitfire Mk V reached 400 mph, and he got it all wrong about the ailerons (109A-E had plain type ailerons, F-K had Frise type ailerons, and all Spits - maybe post-war versions didn't? - had Frise.)

The only really good point is about roll inertia, the 109 indeed seem to have been praised for brisk aileron control (that means, quick response, not neccessarily the same as maximum rate of roll) at low to medium speeds. And of course the 109 benefited from its high-lift devices on the wing in numerous ways, but the main thing about the 109-p51 climb rate difference was obviously that the latter was about a ton heavier.

I noticed that, too (roll performance). To continue in this vein, as the speed of the 109 picked up during development and the initial roll response dropped off due to less aileron deflection per pound force (at the stick) the guns were removed from the wings (F model) to bring the initial roll response (not to be confused with sustained roll) back up. No further action was taken on addressing high speed roll performance until server tabs were developed for the K (et al) but not uniformly applied and as a rule disabled when installed.

Do you know who developed the servo tabs?

[Kurfürst]

IMHO the main thing that effect roll response is the change in wing shape and aileron layout. The wing of the 109A-E was different from the 109F-K, and so was aileron layout. As noted, A-E had plain type of ailerons, and it seems from accounts it was brisker than the F-K. This may be down to the shape/size of aileron and its placement, as after all, what the ailerons do is changing the lift on the wings (increasing on one wing, decresing on the other, hence the roll).

The F-K had Frise type ailerons, which by their nature help to reduce aileron forces (Frise type ailerons have their hinge point moved slightly backwards, and the leading edge of the aileron protounds when deflected into the airstream, which helps a bit.)

As for the Flettners tabs on ailerons, these primary found on photographic evidence mounted on WNF (Wiener-Neustadt, near Vienna, Austria) produced Bf 109G-6/14 and G-10. I have some docs relating to this, trials showed that the effect was that 2/3s aileron deflection was possible at at around Mach 0,70+. WNF did not produce 109K however, only Mtt Regensburg did. The K was supposed to have them, but its difficult to find pictures with them. Perhaps it was mounted, but there are too few pictures of Ks sadly. What the K had however was increased gear ratio on the elevator (elevator deflection was reduced), hence stick forces in pitch decreased.